Missing updates on continuous resize

[bonefish]

hrev35591

On a slow machine with slow graphics, continuous resizing can postpone redraws indefinitely. E.g. test in qemu without kernel acceleration. The larger the virtual screen the better.

• Start a Terminal and run something like while true; do cat /etc/termcap; done.
• Start a second Terminal and run the same.
• Resize the second Terminal window continuously.

With some experimenting one can find a resize rate at which the window isn't updated at all for seconds.